Nippon Steel Corporation

Nhk Spring Co., Ltd.

Aisin Corporation

Nippon Steel Sg Wire Co., Ltd.

Yoichi Oi

Yutaka Neishi

Tatsuro Ochi

Shoichi Suzuki

Fumio Takahashi

Shinya Teramoto

Shuji Kozawa

Michimasa Aono

Shigekazu Nishimoto

Mitsuhiro Kondo

Naoki Takabayashi

Junji Tanaka

A damper spring having an excellent fatigue limit is provided. A damper spring according to the present embodiment includes a nitrided layer formed in an outer layer, and a core portion that is further inward than the nitrided layer. The chemical composition of the core portion consists of, in mass %, C: 0.53 to 0.59%, Si: 2.51 to 2.90%, Mn: 0.70 to 0.85%, P: 0.020% or less, S: 0.020% or less, Cr: 1.40 to 1.70%, Mo: 0.17 to 0.53%, V: 0.23 to 0.33%, Cu: 0.050% or less, Ni: 0.050% or less, Al: 0.0050% or less, Ti: 0.050% or less, N: 0.0070% or less, and Nb: 0 to 0.020%, with the balance being Fe and impurities. In the core portion, a number density of V-based precipitates having a maximum diameter ranging from 2 to 10 nm is 500 to 8000 pieces/μm.

Damper spring

Growing community of inventors

Kariya, Japan

Yoichi Oi